Commitments and Contingencies (Details Narrative) - USD ($)			1 Months Ended								3 Months Ended		9 Months Ended		12 Months Ended
	Dec. 02, 2019	Dec. 03, 2018	Apr. 30, 2020	Feb. 18, 2020	Nov. 27, 2019	Nov. 25, 2019	Nov. 24, 2019	Nov. 22, 2019	Aug. 22, 2017	Dec. 31, 2011	Apr. 30, 2020	Apr. 30, 2019	Apr. 30, 2020	Apr. 30, 2019	Nov. 16, 2012	Mar. 04, 2020	Sep. 30, 2019	Aug. 31, 2019	Jul. 31, 2019	May 31, 2019	Feb. 28, 2019	Jan. 24, 2019	Dec. 02, 2018	Oct. 26, 2018
Commitments and Contingencies									The letter from AEXG counsel claimed that Generex’ acceptance of $3,000,000 in financing from Pharma Trials, LLC, in March 2017, violated the provisions of the MOU prohibiting Generex from seeking other financing, with certain exceptions, for a period of 60 days after execution of the MOU. AEXG has demanded at least $210,000 in cash and 84,000 warrants for Generex stock convertible at $2.50 per share, for attorney’s fees and costs.
Litigation awards for damages		$ 315,695
Litigation awards, exercisable shares																							84,000
Exercise price																							$ 2.50
Note amount			$ 3,748,744								$ 3,748,744	$ 1,060,000	$ 3,748,744	$ 1,060,000			$ 2,222,500	$ 1,150,000	$ 446,600	$ 2,000,000	$ 1,500,000	$ 530,000		$ 682,000
Accrued Liquidated damages			285,613								285,613		285,613
Accrued claim			2,752,235								2,752,235		2,752,235
Attorney's fees													210,000
Legal fees													93,304
Legal cost													12,393
Research and development											332,029	472,010	1,270,600	1,463,015
Breakup fee													2,000,000
Payable to foundation for services			1,315,817								1,315,817		1,315,817						1,315,817
Interest payable to foundation			3,682,812								3,682,812		3,682,812						$ 3,055,945
Interest accrued payable to foundation											218,360	$ 182,629	626,867	$ 524,303
KSKZ Management [Member]
Consulting fees	$ 3,450,000
Damages				$ 2,475,000
ALTuCELL [Member]
Common stock description								ALTuCELL Stock, Generex will issue to ALTuCELL 2,240,000 shares of Generex common stock with an attributed value of $4 million to be issued at the market price of the day at closing, but no less than $0.89 per share. The Company will also pay $2.5 million in cash of which $212,000 has already been paid. In addition to stock and cash at closing, Generex has agreed to pay up to an aggregate of $3,500,000 to ALTuCELL upon ALTuCELL’s attainment of certain milestones.
Advanced to related party			212,000								$ 212,000		$ 212,000
Discover Growth Fund [Member]
Accrued claim																$ 2,200,000
Damages for Unpaid Invoices
Value of damages sought										$ 429,000
Lawsuit filing date										31-Dec-11
Name of Plaintiff										Vendor
Settlement of litigation															$ 125,000
Interest per annum, failure to pay settlement										3.00%
Fixed cost per annum, failure to pay settlement										$ 25,000
Breach of contract and detinue
Counterclaim proceeding										$ 200,000
Olaregen
Intellectual property acquired					$ 650,000
NGIO
Related party cost			1,000,000
Service fees			325,000
NSABP [Member] | Clinical trial agreement [Member]
Research and development			$ 340,000
Alternative Execution Group [Member]
Memorandum of Understanding description		The petition includes a demand of $3,300,360 as the value of the warrants. The arbitrator did not award the specific amount of $3.5 million, but only liquidated damages in the amount of $210,000 and the value of 84,000 warrants “as of today” (the date of the award) plus attorney’s fees, certain costs, prejudgment and post-judgment interest (which continues to run on a daily basis) and arbitration fees.
Olaregen
Stock Purchase Agreement description							Company amended the Stock Purchase Agreement with Olaregen. The Company was obligated to pay in full $11,600,000 to Olaregen by November 30, 2019, in connection with the purchase of Olaregen capital stock. Effective November 24, 2019, the deadline was extended to January 31, 2020.
Regentys
Stock Purchase Agreement description						Company amended the Stock Purchase Agreement with Regentys originally on January 7, 2019. Effective November 25, 2019, the remaining three payments of $2,039,001, $2,000,000, and $3,000,000 are all payable on or before December 30, 2019.